1. Field of the Invention
The present disclosure relates generally to diffusion devices and, more particularly, to diffusion devices that include an odor sensor.
2. Description of the Background of the Invention
Diffusion devices or dispensers are used to disperse volatile materials such as perfumes, deodorizers, insecticides, insect repellants, and the like. Many such devices are passive diffusion devices that require only ambient air flow to disperse the volatile material. Other devices are active diffusion devices that may include a heating element for heating a volatile material to promote vaporization thereof. Other active diffusion devices employ a fan to generate air flow to direct the volatile material out of the diffusion device and into the surrounding environment. Still other diffusion devices utilize an ultrasonic transducer to break up a liquid volatile material into droplets that are ejected from the device.
In light of the wide variety of diffusion devices, a need has developed to control the amount of volatile material that is dispensed into the environment. For example, a passive device will merely disperse the volatile material in an uncontrolled manner even during periods when the benefits of the volatile material are not being experienced, e.g., if a perfume is being dispersed into an empty room or into a room that already has a sufficient level of the perfume. Some of the diffusion devices mentioned above address this issue through the use of odor sensors to sense malodors, e.g., sulfur or cigarette smoke, wherein the diffusion devices are controlled to disperse a volatile material in response to the detection of such malodors. However, typical diffusion devices with odor sensors are complex because such sensors are designed to sense a wide range of chemicals that comprise a multitude of malodors, e.g., hydrogen sulfide, methanethiol, dimethyl sulfide, ammonia, nitrogen dioxide, carbon monoxide, etc. The complexity of such odor sensors affects the size, cost, and implementation of such diffusion devices. Further, many of these known diffusion devices do not employ a mechanism to prevent the dispensing of an inappropriate volatile material that has been inadvertently placed into the diffusion device. Utilization of an inappropriate volatile material may harm the diffusion device because of an incompatibility with a reservoir containing the material or may result in user dissatisfaction by having an incorrect volatile material dispensed into an airspace. Therefore, a need exists for an improvement over prior art diffusion devices that employ odor sensors.